WASHINGTON (AP) — Documents filed by Mitt Romney's former company conflict with the Republican presidential candidate's statements about when he gave up control of the private equity firm Bain Capital. President Barack Obama's campaign seized on the discrepancies Thursday to charge that Romney was lying about his background.

Romney, in turn, said Obama was the one being dishonest, rolling out a hard-hitting television ad that accused the president of launching "misleading, unfair and untrue" attacks about the Republican's role in outsourcing U.S. jobs.

"When a president doesn't tell the truth, how can we trust him to lead?" the narrator says in the Romney ad titled "No Evidence."

Obama has accused Romney of being an "outsourcing pioneer" who invested in companies that shipped jobs to China, India and elsewhere overseas. But Romney, who has made his business experience the central part of his candidacy, claims he had no role in outsourcing U.S. jobs because much of that activity didn't happen until after 1999, when he says he had given up operational control at Bain.

Both candidates dug in on their positions, dispatching aides to level deeply personal criticisms aimed at casting each opponent as little more than a typical politician. Each candidate is seeking to sully his rival's integrity in hopes of gaining ground in closely contested campaign four months before Election Day. But the strategy carries risks: It could alienate voters — especially critical independents — who are turned off by negative campaigning and want to see the candidates focus on the economy and job growth.

At issue is when Romney left Bain, and whether he was at the helm when it sent jobs overseas.

The documents, filed with the U.S. Securities and Exchange Commission, place Romney in charge of Bain from 1999 to 2001, a period in which the company outsourced jobs and ran companies that fell into bankruptcy.

Romney has tried to distance himself from this period in Bain's history, saying on financial disclosure forms he had no active role in Bain as of February 1999. Obama has labeled Romney a job killer in hopes of undercutting the Republican's claim that his private business experience gives him the ability to turn around the struggling economy.

But at least three times since then, Bain listed Romney as the company's "controlling person," as well as its "sole shareholder, sole director, chief executive officer and president." And one of those documents — as late as February 2001 — lists Romney's "principal occupation" was as Bain's managing director.

The Obama campaign called the SEC documents detailing Romney's role post-1999 a "big Bain lie." And Obama deputy campaign manager Stephanie Cutter said the presumptive GOP nominee may have even engaged in illegal activity.

"Either Mitt Romney, through his own words and his own signature, was misrepresenting his position at Bain to the SEC, which is a felony," Cutter said, "or he is misrepresenting his position at Bain to the American people to avoid responsibility for some of the consequences of his investments."

Countering, Romney campaign manager Matt Rhoades said Cutter's comments marked "a new low" in the campaign and called on the president to apologize for "the out-of-control behavior of his staff, which demeans the office he holds."

After weeks of Bain attacks by Obama, Romney rolled out his new ad alleging dishonesty — a signal that the Democratic criticism may be hurting him.

The ad sought to establish dishonesty as a pattern for Obama, and uses his 2008 Democratic primary rival, Hillary Rodham Clinton, to do it. It included a clip of Clinton — now serving Obama as secretary of state — saying, "Shame on you, Barack Obama" and calling on her then-challenger to stop running dishonest ads.

Even as it sought the upper hand with the ad, Romney's campaign found itself scrambling to explain the apparent discrepancies between the former Massachusetts governor's past statements about his Bain tenure and the SEC documents.

Campaign spokeswoman Andrea Saul insisted Romney left Bain in February 1999 and "had no input on investments or management of companies after that point."

The campaign also issued a statement from Bain saying that "due to the sudden nature of Mr. Romney's departure, he remained the sole stockholder for a time while formal ownership was being documented and transferred to the group of partners who took over management of the firm in 1999. Accordingly, Mr. Romney was reported in various capacities on SEC filings during this period."

The SEC documents — which have received modest attention despite being reported in recent days by publications including the political website Talking Points Memo — raise questions about Romney's role at Bain in 1999, 2000 and early 2001. If he turned his full attention to the Olympics in early 1999, as his campaign says, it's hard to square with the Bain SEC filing, two years later, listing his "principal occupation" as the company's managing director and his titles as CEO and president.

James Cox, a securities law professor at Duke University, said the SEC's Schedule 13D forms have always been under legal scrutiny by SEC officials and company executives. He said law firms hired to file such reports — known as "beneficial ownership reports" because they deem who can sell securities — "pay great attention to these forms. I don't find that these parts of the documents are casually reported."

"It's hard for me to believe you could be listed as 'management anything' without it taking up a bulk of your time," said Cox, who had not reviewed Bain's statement on Thursday.

During the years in question — 1999 to 2011 — Bain oversaw investments that either sent jobs abroad of filed for bankruptcy. For example, in late 1999, Bain-controlled Steam International set up overseas call centers, and a subsidiary moved jobs from California to Mexico. In 2000, the Ampad company declared bankruptcy. The following year, so did steel-maker GS Industries — just as Bain made $58.4 million from its investment.

The Obama campaign has used workers laid off from Ampad in attacks on Romney's business record.

Romney helped found Bain Capital in 1984. The private equity firm invested in various companies, often restructuring their management and operations. Some became success stories that hired new workers and enriched Bain's investors. Others struggled or went out of business. Romney made millions of dollars and cites Bain as chief proof that he understands private enterprise and job-creation.

Romney eventually negotiated a retirement agreement with Bain Capital in 2002. The agreement was made retroactive to February 1999.

The Boston Globe reported Thursday that a Massachusetts financial disclosure form Romney filed in 2003 stated he still owned 100 percent of Bain Capital in 2002. Romney was elected to one term as Massachusetts governor in 2002.